Dual polarization microwave energy phase shifter for phased array antenna systems

ABSTRACT

A phase shifter is disclosed for supporting dual orthogonal polarization modes of propagated microwave energy in tactical electrically beam scanning phased array antenna systems of the optically fed reflector type. Reentrant single port antenna array elements provide a predetermined electrical phase shift of linear as well as circular polarized energy. Incident waves received by each element oriented in one plane of polarization, for example, a vertical wave, will be electrically shifted and launched after traversal of the device as, illustratively, a horizontally oriented wave. Each element incorporates a circular polarizer as well as reflective termination member together with solid state phase shifting means.

United States Patent [72] Inventor Willard W. McLeod, Jr.

Lexington, Mass.

[211 App]. No. 693,531

[22] Filed Dec. 26, 1967 [45] Patented Mar. 9, 1971 [73] AssigneeRaytheon Company Lexington, Mass.

[5 4] DUAL POLARIZATION MICROWAVE ENERGY PHASE SHIFTER FOR PHASED ARRAYANTENNA SYSTEMS 12 Claims, 12 Drawing Figs.

[52] US. Cl. 343/754,

333/21, 333/24.1, 333/24.3, 333/98, 343/756, 343/778, 343/854 [51] Int.Cl 1101p 1/16, H03h 5/12, I-I0lg 19/06 [50] Field of Search 343/754-756, 854, 778, 909 (curso y); 333/24.l, 24.3, 21 (A), 21

[56] References Cited UNITED STATES PATENTS 3,100,287 8/1963 Scharfmanet al. 333/24.1

3,109,152 10/1963 Dachert 343/778 3,154,784 10/1964 Allen 343/183,161,879 12/1964 l-Iannan et al 343/756X 3,162,828 12/1964 Schmidt eta1. 343/756X 3,166,724 l/1965 Allen 333/24.1

3,277,401 10/1966 Stern 333/24.3X

3,290,624 12/1966 Hines 333/31 3,305,867 2/1967 Miccioli et a1. 343/754XDC BIAS VOLTAGE SOURCE Frank et al., Latching Ferrite Phase Shifter forPhased Arrays, The Microwave Journal March 1967, pp. 97- 102 Nolen, .I.C., Phased Array Polarization Agility IEEE Trans. on Antennas &Propagation, Vol. AP- 13, 1965 pp. 820- 821 Primary Examiner-EliLieberman Assistant Examiner-Wm. l-I. Punter Attorneys-Harold A. Murphy,Joseph D. Pannone and Edgar O. Rost ABSTRACT: A phase shifter isdisclosed for supporting dual orthogonal polarization modes ofpropagated microwave energy in tactical electrically beam scanningphased array antenna systems of the optically fed reflector type.Reentrant single port antenna array elements provide a predeterminedelectrical phase shift of linear as well as circular polarized energy.Incident waves received by each element oriented in one plane ofpolarization, for example, a vertical wave, will be electrically shiftedand launched after traversal of the device as, illustratively, ahorizontally oriented wave. Each element incorporates a circularpolarizer as well as reflective termination member together with solidstate phase shifting means.

PATENTEDHAR 91971 2 3.569374 sum 1 UF 3 \4 SHlFTER FEED F/G j PRIOR ARTF/GZ PRIOR ART l5 A? 9 PROGRAMMER o QTRANSM|TTER FIG 3 PRIOR ARTRECEIVER I '1 I SOLID STATE CIRCULAR REFLECTIVE 8 PHASE SHIFTERPOLARIZER TERMINATION 20 meREss PATH 4 2/ OFENERGY 23 ,1 \22 $224 25 22V A 24 2 24 $00 1w H 28 =1a0 7 J 28% EGRESS PATH 27 OF ENERGY INVENTORE7 5 WILLARD 024M500, .15:

ATTORNEY PATENTEDMAR SIB?! 3569-874 SHEET 2 0F 3 I 5 I I I INVENTORWILLARD n. McLEOD, JR.

A T 7' ORA/E) PRIOR ART F WAVE PATENTED'HAR EH97! SHEET 3 OF 3 CIRCULARPHASE CIRCULAR REFLECTWE POLARIZER SHIFTER POLARIZER TERMINATIONM/VE/VTUR WILLARD W. MCLEOD, JR.

.4 TTOR/VE Y DUAL POLARIZATION MICROWAVE ENERGY PHASE SliIFTEl-Ri FORIETASED ARRAY ANTENNA SYSTEMS BACKGROUND OF THE INVENTION The presentinvention relates to electronically beam scanning radar antennas whichrequire substantially less mechanical moving parts than prior artstructures. Planar antennas utilizing a considerable quantity ofsteering elements individually providing variable electrical lengths tocollimate and direct high power electromagnetic wave energy in apredetermined wave front at veryrapid rates of speed. Each antennasteering element requires at least one phase shifting member togetherwith means for accurately and rapidly controlling the predeterminedelectrical phase shift. In the prior art numerous devices have beensuggested for the accomplishment of the required electrical phase shiftincluding the use of discrete bodies of ferromagnetic materials, alsoreferred to as ferrites, which are magnetized by external electricalcoils to vary the RF permeability characteristics of the selectedmaterial. An excellent dissertation on the applicable antenna systems aswell as prior art phase shifting devices may be found in the referenceSurvey of Electronically Scanned Antennas", parts 1 and 2, by HaroldS-hnitkin, The Microwave Journal, Dec. 1960, pgs. 67-72, and Jan.196l,pgs. 57-64.

The numerous antenna beam steering elements have been coupled toindividual high power microwave transmission elements with the beamdirection being determined by a computerized programmer. Such systemsrequire complex corporate structures to couple the high power microwaveenergy source to the antenna radiating elements and is referred to inthe art as a transmission type phase array antenna system. In U.S. Pat.No. 3,305,867, issued Feb. 21, 1967 to Aldo R. Miccioli et a]. entitledAntenna Array System a new concept in phased array antenna systems isdisclosed which involves a large array of passive elements optically fedfrom a physically and conceptually separate radiant energy generationsource. Each of the antenna passive elements include phase shifter meanstogether with a single port reentrant radiating element to col-Iectively define the beam steering components. High power microwaveenergy is transmitted through free space to illuminate the phased arrayantenna system and thereby eliminate the numerous transmission linesrequired in prior art antenna systems for directly feeding each element.The disclosed optically fed antenna array system referred to in theaforementioned patent is also capable of being utilized for bothtransmission and reception with the duplexing accomplished in aconventional manner by a single high power antenna horn and a transducermechanism to switch the horn to a receive mode after a transmissioncycle. This antenna array system is commonly referred to as thereflector type and the beam steering elements provide for the traversalof the received electromag netic waves in two directions within eachantenna element while receiving the appropriate variable electricalphase shifts.

In an article appearing in the IEEE Transactions on Antennas andPropagation, Sept. 1965, Vol. AP-I 3, pgs. 820- 82l, authorized by JohnC. Nolen, attention is directed to phased array polarization agility.The referenced article mentions a simple method of obtaining dualpolarization capabilities from a single phase shifter phased arrayelement utilizing one set of reciprocal phase shifting devices togetherwith serially connected dual antenna elements. Linearly polarized wavesin either the horizontal or vertical mode will excite an appropriateantenna dipole feed and be transmitted through the phase shifting deviceto another antenna dipole element oriented perpendicular to the firstreceiving element. The problem of simultaneously processing dualorthogonal modes is one of considerable interest in phased array antennasystems. The reductions in weight as well as cost through theutilization of single phase shifting means to handle both orthogonalpolarizations, particularly in view of the large number of antennaelements employed, points up the desirability of solutions to theproblem of orthogonal wave propagation for reflector type optically fedphased array antenna systems.

SUMMARY OF THE INVENTION in accordance with the teachings of the presentinvention a single phase shifting antenna element is provided to handleelectromagnetic wave energy in either the horizontal or vertical planeof orientation. The implementation of the invention incorporates theutilization in the phase shifter of a short circuit reflectivetermination at one end of the antenna element coupled with polarizationinversion means or a circular polarizer. In an illustrative embodimentutilizing a semicom ductor diode phase shifter, a linearly polarizedwave having the E-field vector oriented in a predetermined manner willbe propagated and launched with an electrical phase shift andorientation orthogonal to the input wave. In another illustrativeembodiment of the invention a single port reentrant phase shifter isdisclosed utilizing ferromagnetic materials of the closed magnetic loopvariety together with digital latching conductors for switching betweenthe binary remanent magnetization states. W

A simplified phase shifting antenna element for electronically scannedphase array antennas has evolved having a dual polarization modecapability. Use is made of present day known phase shifting means toprovide a reciprocal type phase shifting device for use in dual modeantennas of the type shown in the above referenced article by Nolen.

BRIEF DESCRIPTION OF THE DRAWINGS The invention, as well as the specificdetails of the construction of a preferred illustrative embodiment, willnow. be described, reference being directed to the accompanyingdrawings, in which:

FIG. l is a diagrammatic representation exemplary of a prior art dualpolarization antenna element;

FIG. 2 is a diagrammatic presentation of an antenna array systemutilizing cross-polarized elements;

FIG. 3 is a diagrammatic view of a phased array antenna system of theoptically fed reflector type;

FIG. 4 is a block diagram illustrative of an embodiment of theinvention;

FIG. 5 is a diagrammatic presentation of the vectorial distribution ofthe polarized waves traversing the embodiment of the invention;

FIG. 6 is a perspective view partly in section of the embodi ment of thepresent invention utilizing semiconductor diode phase shifting means;

FIGS. 7 and 3 are diagrammatic illustrations of the orientation of thesemiconductor diode phase shifting means and an alternative arrangement,respectively, of the embodiment of the invention;

FIG. 9 is a partial perspective view of a digital latching ferritedevice utilized in the prior art;

FIG. it) is a perspective view partly in section of the embodiment ofthe invention utilizing a digital latching ferrite phase shifter;

FIG. ll is a block diagram of an alternative arrangement utilizing thepropagation of circularly polarized electromagnetic wave energy; and

FIG. l2 is a perspective view of a radiating element utilized with acircular waveguide antenna steering device. DESCRIP- TION OF THEPREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, a system forpropagating dual polarization modes utilizing a single seriallyconnected phase shifter is illustrated and denoted by numeral 1. Antennadipole 2 is disposed in a vertical manner and hence all waves orientedin this plane will be propagated. The orthogonal antenna dipole 3 willbe utilized for the horizontally polarized waves.

A reciprocal phase shifter 4 is serially connected between both antennadipole elements which may be supported along a planar direction'by areflector member 5 in a columnar array.

In accordance with the teachings of this method of wave transmission,energy of one polarization enters the antenna dipole member, traversesthe phase shifter and is launched again in the orthogonal polarization.If the horizontally polarized waves are propagated then the horizontalreflector elements 3 are excited. After traversing the phase shiftingmeans the radiated energy leaves by means of the vertically polarizedantenna elements 2. Any mismatch in the antenna elements or phaseshifters returns the illumination to the first antenna element excitedor in this instance the horizontal element. For reverse polarized wavesthe orthogonal antenna element will be excited and the signal paththrough the phase shifter will be in the reverse direction. As a resulta single phase shifter will serve both polarizations utilizing areciprocal energy propagation means. A problem in the prior art exists,however, in that reciprocal element phase shifters present additionalproblems and may be more costly. Accordingly, the present inventionseeks to achieve the dual polarization propagation of orthogonalpolarization modes impart reciprocity in phase shifting values withsolid state materials which are inherently nonreciprocal.

Referring next to FIG. 3, the deployment of the invention in a phasedarray antenna system of the optically fed reflector type will bedescribed. A plurality of single port reentrant antenna beam steeringelements 6, each incorporating a phase shifter, collectively define thearray antenna 7. A radiating element 8 is provided at the entrance ofeach antenna element for ingress of the uncollimated energy and egressof the appropriately shifted signals of the electronically steered beam.A high power microwave energy generator 9 is spatially disposed from thearray antenna and the energy is radiated by means of a horn 10 of wellknown construction. In order that theoverall system may be utilized induplexing of transmit and receive signals a two mode transducer 11 iscoupled to the horn through a circular polarizer 12. In such operation asuitable receiver 13 will be coupled to the same antenna horn 10.

Each antenna steering element 6 will provide a predetermined degree ofphase shift by means of leads 14 coupled to a computerized programmer 15so as to electrically vary the effective electrical length of eachelement. The energy from transmitter horn 10 is directed toward thearray antenna radiators 8 in a divergent beam designated A in theillustration. Each antenna element in the array is reentrant andterminated by reflective ends provided by short circuit means 16. Thereceived energy after traversing each antenna element in a first andsecond reverse direction is emitted as a collimated beam having a planarwave front of uniform phase designated by the letter B. Any desiredamount of angularity of the beam wave front may be achieved throughadjustment of the individual element phase shifting means. The beamdirection is designated by arrow C and it is evident that the energyemanating from this direction will be reflected by scanned targets backtoward the array antenna 7 where it will be received, phase shifted andretransmitted through the antenna horn 10 to the receiver 13. Theadvantage of the reflector type optically fed phase array antenna systemis that the individual antenna steering elements serve a dual functionof transmitting and receiving utilizing a single unitary structure whichis rapidly controlled electronically.

Referring now to FIG. 4, the teachings of the present invention comprisethe provision of an antenna element 18 for receiving and transmittingcoupled to a solid-state phase shifting means 19 disposed within awaveguide section adapted to support and propagate linearly polarizedwaves having orthogonal electric field vectorial components.Illustratively, square waveguide will support such orthogonaldistribution of the electromagnetic wave energy. Immediately followingthe phase shifter section is a circular polarizer or polarizationinverter 20 such as for example acne-quarter wavelength plate memberwhereby a selective delay in phase of 90 in one orthogonal direction isapplied to the linearly polarized waves. The circular polarizer section20 is followed by the reflective termination 21 in the form of ametallic short circuit member enclosing one end of the square waveguidesection.

The mechanics of operation of the combined structure will now bedescribed, reference being directed to FIG. 5. In this illustration theblock diagram components of the embodiment of the invention shown inFIG. 4 have been similarly designated for the sake of clarity. Eachvector diagram is depicted for the position of a person standing at aparticular point and looking in the direction of the energy travel. Aplane linearly polarized wave having a vertical electric field vectorcomponent indicated by the arrow 22 will be received by antenna element18 which is adapted to receive linearly polarized energy in eitherorthogonal component and for launching the energy in the cross-polarizedvector. Within the phase shifter 15 vertical wave 22 receives apredetermined degree of phase shift designated by symbol 1 and arrow 23if the orientation of the vector is in a predetermined plane withrespect to the phase shifting means. In a semiconductor diodetype ofphase shifter with the diode element oriented parallel to theorientation of the E-field vector 22 an appropriate phase shift would beapplied on entrance to the phase shifter. If the E-field vector ishorizontal then the phase shift takes place only on exit of the energy.For the sake of clarity in the explanation of the operation of thestructure the degree of phase shift in the illustrated vector will bepurposely omitted and the E-field vector will be resolved into itsorthogonal component vectors designated by the arrows 24 and 25. In thenext or circular polarizer section 20 with a quarter wave plate similarto the one designated by the numeral 41 oriented 45 as shown in FIGS. 6and 7; vector 24 which is now shown as a solid line is allowed topropagate while vector 25 shown as a dotted line is delayed. As aresult, vector 24 is ahead of vector 25 and contacts the short circuitedend 21 ahead of vector 25 for a second traversal. The reflected wavefrom the short circuit means which may be referred to as the backwardwave becomes a mirror image of the original wave and vector 25 is nowspatially oriented another 90 or a total of outof-phase with respect toits companion wave vector 24 after the second pass through polarizer 20.As is well known in the microwave transmission art, orthogonal componenthaving a 180 phase differential may now be represented by the solid linevector 27 which combines with the original orthogonal component 24 toform the combined vector 28 which is now cross-polarized or horizontalto the original incident vertical wave. However, since it is inherent inthe teachings of the invention that the phase shift means are orientedin a predetermined manner the incidence of the wave in the horizontalvector will result in no phase shift taking place upon traversal of thephase shift section for; the second time. Vector 28 in the horizontalorientation with the original value of phase shift provided during thefirst traversal will therefore be launched by antenna element 18. Anyreflected energy from a distant target will traverse the embodiment ofthe invention in exactly the reverse manner. For horizontal linearlypolarized signals incident upon the antenna element the emitted wavewill assume an orthogonal cross-polarization as a vertical wave. In thisexample the phase shift occurs only when the electric field vector isoriented parallel to the plane of orientation of the phase shiftingelement upon exit of the energy.

Referring now to FIG. 6 and an operative embodiment, square waveguidesection 30 having flange members 31 and 32 appended adjacent the endsthereof houses the solid state phase shifter means. In this embodiment asemiconductor diode member generically designated 33 is suitably biasedby a DC voltage source 34 to render the diode means in the appropriatestate dependent on the incident electromagnetic energy received by theoverall antenna steering element. Suitable semiconductor phase shiftingmeans comprise any of the well known silicon crystal or PN junction,varactor diodes, as well as members of the avalanche transit time diodedevice family. An example of such a device is the PIN diode wherein anintrinsic region is provided between the P and N junctions to form ahigh reverse current device which exhibits negative resistance whenoperated at a high electrical bias. Such a diode phase shifter may besupported within a conductive column 35 and biasing source 34 is coupledthrough the conductor by means of terminals 36. With a high RF currentoriented in a direction parallel to the plane of the column such energyis properly oriented with respect to the biased conductor and will beappropriately phase shifted. Conversely, the orientation of theelectromagnetic wave in the orthogonal or horizontal direction resultsin no RF current in the intrinsic region of the diode member and nophase shift is applied to the wave energy.

For the purposes of the understanding of the specification the termphase shdting means shall be interpreted to designate any device forintroducing a predetermined value of electrical phase shift one linearlyoriented plane of wave transmission and another phase shift uponincidence of wave energy in the orthogonal plane of transmission.

Following the phase shifter section is a companion square waveguide.section Elli having flanges 39 and ill appended thereto. A one-quarterwave conductive plate member 41 is disposed within the waveguide 38 tochange the spatial orientation of the horizontal and vertical electricfield vectors and is positioned diametrically at an angle ofapproximately 45 in the manner of such circular polarizers employed inwave transmission devices. A card or vane of a dielectric material maybe similarly employed in lieu of the member 41. The structure iscompleted by the provision of a shorting plate member 42 enclosing theend of waveguide section 38 and secured to flange member 40.

it is understood that the antenna elements for the reception as well astransmission of electromagnetic wave energy are well known in the artand may be coupled to the flange member Ell. No specific details havetherefore been enumerated herein.

in FIG. 7 the inline orientation viewed from the open waveguide antennaend is pictorially represented with similar numerals identifying thestructure shown in FIG. 6. in FIG. 8 a modification of this combinationis illustrated with the semiconductor phase shifter diode elements 33and 44 orthogonally oriented within conductive post members Q and 4-6.This modification provides for the possibility of requiring onlyone'half of the phase shift value to be applied to the waves oriented inthe horizontal plane and the other half to the waves oriented in thevertical plane with the total phase shift being the sum of the twovalues. This structure will result in a substantial reduction in thelength of the overall phase shifter required together with anaccompanying reduction in weight. Such a dual polarization device couldhave possible applications in transmission modes of propagating energywherein the circular polarizer and short circuit means are eliminatedand the device will be capable of receiving energy at one end andlaunching it at the opposing end into free space.

FlG. 9 is illustrative of prior art digital ferrite latching phaseshifting means disposed along the longitudinal axis of a rectangularwaveguide transmission section 51. The closed magnetic circuit looptoroid body member 50 of a ferromagnetic material is provided with adirect current conductor 52 extending through a passageway 53 in thetoroid body member. The magnetic closed loop is indicated by the arrows54 and 55 with the direction representing the magnetization induced bythe passage of direct current pulses in the direction designated by thearrow 56. Due to the fact that the magnetic path is a closed loop,demagnetizing effects are relatively absent and the selected magneticmaterial is said to be in a remanent magnetization state. The toroidgeometry also provides a reasonably square hysteresis magnetizationloop. Reversal of the direction of the current pulse results in thelatching or induction of the second remanent magnetization state withthe direction of the magnetic flux lines reversed and directed in acounterclockwise manner. The resultant phase shift of electromagneticwave energy propagated through rectangular waveguide 51 is determined bythe properties and geometry of the ferromagnetic material and theorientation of the direct current magnetization with respect to thedirection of the RF propagated energy which in the first instance isindicated as a vertically polarized wave designated by the arrow 57. inthe employment of digital latching phase shifter ferromagnetic means theoperation provides a net overall phase shift in that the reversedirected wave which has a different plane of orientation with respect tothe direction of magnetization will not receive an equivalent reversephase shift. The same net overall phase shift will be realized for bothorthogonal components so that the device provides for reciprocaloperation. The presence of the ferromagnetic material, however, doesintroduce some attenuation of the redirected wave energy. Suchattenuation may be compensated for and may even be a distinct advantagein certain transmission systems.

In FIG. 10 a complete embodiment of an antenna steering elementutilizing a digital latching ferrite phase shifter is disclosed insquare waveguide 58 having mounting flanges 59 and 60. A substantiallysquare toroid body 61 of the preferred ferromagnetic material isdisposed along the longitudinal axis of waveguide 58. The electricallength of the toroid body member 61 is selected to provide apredetermined phase shift in one remanent magnetization state and adifferent value of phase shift in the second remanent magnetizationstate and a different value of phase shift in the second remanentmagnetization state. conventionally, such toroid body members maycomprise a plurality of body members having varying electrical lengthsand referred to as bits" in tandem arrays to collectively provide anydesired total phase shift. Hence, a first body member could provide alatch and subsequent body members provide a 45 or 22-/2latch. Anycombination of the toroid bodies in each of the antenna steeringelements will provide the individual varying electrical phase shifts.Abutting the opposing ends of the toroid member 61 are nonmagneticdielectric spacers 62 and 63 which serve as matching transformer meansto facilitate the transfer of the electromagnetic microwave energy inspace into the antenna elements. The requisite latching conductor 64 iscentrally disposed within the toroid member 61 and terminates inexternal connection fm means 65 for the application of suitable DCvoltage pulses. Similar conductors and terminal means would be providedfor individual bits provided along the longitudinal axis of thewaveguide. The subsequent section mounted to the phase shifter sectionincludes square waveguide 66, mounting flanges 67 and 68, together withthe: internally and angularly disposed one-quarter wave conductive platemember 69. The The reflective termination means comprising a metallicshort circuiting plate 70 abuts flange 68. ln this embodiment theoperation again is similar to that described in the semiconductor diodephase shifter embodiment. incident waves linearly polarized on oneorthogonal mode will be launched in a crosspolarized plane with a netphase shift due to the required two state operation of the phaseshifting means. The introduction of the ferromagnetic material withinthe waveguide path does result in some attenuation of the returningwaves reflected from the short circuiting end 70. It is thereforesuggested that this phase shifting device be utilized in such systemswhere alternate wave transmissions are in alternate orthogonal modedistributions. Such intermittent cross-polarization operations may alsobe advantageous in certain electronic countermeasure radar systems.

An interesting modification and variation of the subject invention isdisclosed in H6. ii. in the propagation of electromagnetic waves incircular guide both orthogonal components are simultaneously supportedduring the traversal. The circularly polarized energy which illuminatesthe antenna element 71 is indicated by the circular arrow 72. A circularpolarizer member 73 disposed in front of the phase shifter 74 will befollowed by a subsequent circular polarizer 75 and reflectivetermination 76, all disposed within circular waveguide. in thisembodiment the first circular polarizer section may have the one-quarterwave plate oriented orthogonally to h the angular orientation of thecircular polarizer 75 disposed before the reflective termination 76. Thecircularly polarized waves upon. traversal of the first circularpolarizer means will be translated into a linearly polarized wave forentrance into the base shifter 74. If the orientation of the linearlydisposed vector of the wave is properly oriented with regard to thephase shifting means a second traversal through the circular polarizer75 will result in the orientation of the wave in the orthogonal orcrosspolarized mode where a different shift will occur. Circularpolarizer 73 converts the linearly'polarized wave again into a circularwave for retransmission into space by antenna 71. This embodimentprovides a phased array antenna which may be utilized in either thesingle bounce or double bounce radar mode to provide another agilitycharacteristic along with the dual orthogonal mode transmission andenhanced target resolution.

In FIG. 12 antenna radiator means 77 for use with circular waveguide 78type phase shifters are shown. The radiating antenna element 77 ispreferably of a material having the impedance characteristics requiredto transform the free space electromagnetic wave energy to theimpedances of the circular waveguide. Conventionally dielectricmaterials have been selected for this element. A material which has alsobeen widely selected for this purpose is Rexolite or other similarcomposition materials.

The phase shifting means may comprise any of the solid state meansheretofore discussed.

There is thus disclosed a unique and useful dual polarization phasedarray antenna element for phase shifting of the microwave energy. Whilethe description has been concerned primarily with the reflection typeoptically fed reentrant phase shifters some modifications or alterationsevident to those skilled in the art will result in transmission typephase shifters which provide an input and an output end for thepropagation of microwave energy. It is important to bear in mind that asingle phase shifting device may provide for the propogation of energyin orthogonal polarization modes. It will be also obvious to thoseskilled in the art that any number of equivalents may be substituted forthe circular polarizing means to accomplish the purposes of theinvention. While detailed illustrative embodiments have been shown anddescribed herein, it is intended that this description shall beconsidered as exemplary only and not in a limiting sense with respect tothe broader aspects of the invention as defined in the appended claims.

I claim:

1. A dual polarization microwave energy phase shifter comprising:

waveguide means for receiving and propagating linearly polarizedelectromagnetic wave energy having electric field components orientedorthogonally in predetermined polarization planes;

solid-state phase shifting means disposed along the longitudinal axis ofsaid waveguide means for introducing a predetermined value of phaseshift in one orthogonal component of wave transmission and another phaseshift value upon incidence of the wave energy component in the otherorthogonal plane of wave transmission;

circular wave polarization means disposed inline following said phaseshifting means;

conductive means enclosing et the end of said waveguide means adjacentto said circular polarizer means to present a short circuit and reflectsubstantially all said energy incident thereon whereupon one orthogonalcomponent emerges from the circular wave polarization means having aphase delay of 180 relative to its related component after traversals ina forward and reverse direction; and

said reflected energy being propagated having a plane of polarizationoriented orthogonally to the original incident wave energy.

2. A phase shifter according to claim 1 wherein said phase shifter meansinclude semiconductor diode elements.

3. A phase shifter according to claim 1 wherein said phase shiftingmeans include digital latching ferromagnetic elements having binaryremanent magnetization states.

4. A reflector type dual polarization microwave energy phase shiftercomprising:

square waveguide means both for receiving and launching at one open endlinearly polarized electromagnetic wave energy having electric fieldvectors oriented in a predetermined input plane and having orthogonalwave components:

conductive means short-circuiting the opposing end of said waveguidemeans to reverse the direction of travel of wave energy incidentthereon;

solid-state phase shifting means disposed along the longitudinal axis ofsaid waveguide means adjacent to the receiving and launching end forintroducing a predetermined value of phase shift in one orthogonalcomponent of wave energy traveling in one direction and another phaseshift value in the orthogonal component of wave energy traveling in thereverse direction;

circular polarization means disposed between said short circuit meansand said phase shifting means to reflect and reverse the direction oftravel of all wave energy incident thereon; and

said reflected energy to be launched having an output plane ofpolarization orthogonal to the received linearly polarized wave energy.

5. A phase shifter according to claim 4 wherein said phase shiftingmeans include semiconductor diode elements.

6. A phase shifter according to claim 4 wherein said phase shiftingmeans include digital latching ferromagnetic elements having binaryremanent magnetization states.

7. A reflector type dual polarization electrical phase shifting devicecomprising:

square waveguide transmission means adapted to receive and propagatethrough a single port linearly polarized electromagnetic wave energyhaving orthogonal wave components;

solid-state phase shifting means disposed along the longitudinal axis ofsaid waveguide means for introducing a predetermined value of phaseshift in one wave component and another phase shift value upon incidenceof wave energy in the orthogonal wave component;

a one-quarter wavelength angularly disposed conductive vane memberpositioned within the waveguide means following the phase shiftingmeans;

conductive shorting means terminating the end of said waveguide means toreflect substantially all energy incident thereon; and

said reflected energy having a predetermined value of phase shiftdetermined by two traversals through the phase shifting means and alinearly polarized wave in a plane orthogonal to the plane ofpolarization of the received energy.

8. In a reflector type optically fed phased array antenna systemcomprising in combination:

means for generating and transmitting in free space linearly polarizedelectromagnetic wave energy;

means for collimating and directing said energy in a desired directionincluding an array of antenna beam steering elements;

each of said elements comprising a section of square waveguide forreceiving and launching said energy having an electric field orientationin a predetermined plane and having orthogonal wave components;

a radiating element enclosing one end of said waveguide and a conductivereflecting plate member terminating the opposing end;

solid-state phase shifting means disposed along the longitudinal axis ofsaid waveguide behind the radiating element to produce a phase shiftvalue in one orthogonal wave component and a different phase shift valueupon traversal of wave energy in the other orthogonal wave component;

a circular polarizer for inverting the orientation of the electric fieldvectors positioned between the wave-guide termination and phase shiftingmeans; and

said incident linearly polarized received energy and said launched phaseshifted energy being oriented in orthogonal planes to one another.

9. The combination according to claim 8 wherein said phase shiftingmeans include semiconductor diode elements.

10. The combination according to claim 8 wherein saidmined value ofphase shift upon incidence of the orthogonal component traversingin thereverse direction;

conductive shorting means disposed at an end of said waveguide forreversing the direction of travel of substantially all energy incidentthereon; and

a circular polarizer disposed between the shorting means and diode phaseshifting means whereby one orthogonal component emerges from saidpolarizer having a phase delay. of relative to the other componenttraversals in a forward and reverse direction.-

12. A 'dual polarization microwave energy phase shifter comprising:

a single port waveguide means for receiving and launching circularlypolarized electromagnetic wave energy;

solid-state phase shifting means sandwiched between circular wavepolarization means for converting said circularly polarized waves tolinearly polarized waves disposed within said'waveguide;

said conductive reflective termination means enclosing the opposing endof said waveguide; 7

said phase shifting means introducing a predetermined value of phaseshift in only one linearly oriented wave component and substantially noelectrical phase shift in an orthogonally oriented wave componentjandsaid received and launched wave energy having planes of polarizationoriented orthogonal to one another.

It in certified 1514.; ergo: anymore in the above-deanLlfied patent andthat said Letters LQLLQLI: are hereby corrected or; shown melon:

Column 7, Line 57 (Claim 1) After "enclosing" delete "et" Column 7, Line57 (Claim 1) Before "conductive" insert --and--- Column 7, Line 64(Claim 1) After delete "and" Column 8, Line 16 (Claim 4) Before"circular" insert --and- Column 8, Line 19 (Claim 4) After delete "and"Column 8, Line 42 (Claim 7) Before "conductive" insert --and-- Column 8,Line 44 (Claim 7) After delete "and" Column 8, Line 70 (Claim 8) Before"2." insert --and--- Column 8, Line 72 (Claim 8) After delete "and"Column 9, Line 22 (Claim 11) After delete "and" Column 10, Line 1 (Claim11) Before "a" insert --and- Column 10, Line 4 (Claim 11) After"component" insert -after-- Column 10, Line 14 (Claim 12) Before"conductive" delete "said" and insert --and-- Column 10, Line 19 (Claim12) After delete "and" Signed and sealed this 26th day of October 1971(SEAL) Attest:

1. A dual polarization microwave energy phase shifter comprising:waveguide means for receiving and propagating linearly polarizedelectromagnetic wave energy having electric field components orientedorthogonally in predetermined polarization planes; solid-state phaseshifting means disposed along the longitudinal axis of said waveguidemeans for introducing a predetermined value of phase shift in oneorthogonal component of wave transmission and another phase shift valueupon incidence of the wave energy component in the other orthogonalplane of wave transmission; circular wave polarization means disposedinline following said phase shifting means; conductive means enclosinget the end of said waveguide means adjacent to said circular polarizermeans to present a short circuit and reflect substantially all saidenergy incident thereon whereupon one orthogonal component emerges fromthe circular wave polarization means having a phase delay of 180*relative to its related component after traversals in a forward andreverse direction; and said reflected energy being propagated having aplane of polarization oriented orthogonally to the original incidentwave energy.
 2. A phase shifter according to claim 1 wherein said phaseshifter means include semiconductor diode elements.
 3. A phase shifteraccording to claim 1 wherein said phase shifting means include digitallatching ferromagnetic elements having binary remanent magnetizationstates.
 4. A reflector type dual polarization microwave energy phaseshifter comprising: square waveguide means both for receiving andlaunching at one open end linearly polarized electromagnetic wave energyhaving electric field vectors oriented in a predetermined input planeand having orthogonal wave components: conductive means short-circuitingtHe opposing end of said waveguide means to reverse the direction oftravel of wave energy incident thereon; solid-state phase shifting meansdisposed along the longitudinal axis of said waveguide means adjacent tothe receiving and launching end for introducing a predetermined value ofphase shift in one orthogonal component of wave energy traveling in onedirection and another phase shift value in the orthogonal component ofwave energy traveling in the reverse direction; circular polarizationmeans disposed between said short circuit means and said phase shiftingmeans to reflect and reverse the direction of travel of all wave energyincident thereon; and said reflected energy to be launched having anoutput plane of polarization orthogonal to the received linearlypolarized wave energy.
 5. A phase shifter according to claim 4 whereinsaid phase shifting means include semiconductor diode elements.
 6. Aphase shifter according to claim 4 wherein said phase shifting meansinclude digital latching ferromagnetic elements having binary remanentmagnetization states.
 7. A reflector type dual polarization electricalphase shifting device comprising: square waveguide transmission meansadapted to receive and propagate through a single port linearlypolarized electromagnetic wave energy having orthogonal wave components;solid-state phase shifting means disposed along the longitudinal axis ofsaid waveguide means for introducing a predetermined value of phaseshift in one wave component and another phase shift value upon incidenceof wave energy in the orthogonal wave component; a one-quarterwavelength angularly disposed conductive vane member positioned withinthe waveguide means following the phase shifting means; conductiveshorting means terminating the end of said waveguide means to reflectsubstantially all energy incident thereon; and said reflected energyhaving a predetermined value of phase shift determined by two traversalsthrough the phase shifting means and a linearly polarized wave in aplane orthogonal to the plane of polarization of the received energy. 8.In a reflector type optically fed phased array antenna system comprisingin combination: means for generating and transmitting in free spacelinearly polarized electromagnetic wave energy; means for collimatingand directing said energy in a desired direction including an array ofantenna beam steering elements; each of said elements comprising asection of square waveguide for receiving and launching said energyhaving an electric field orientation in a predetermined plane and havingorthogonal wave components; a radiating element enclosing one end ofsaid waveguide and a conductive reflecting plate member terminating theopposing end; solid-state phase shifting means disposed along thelongitudinal axis of said waveguide behind the radiating element toproduce a phase shift value in one orthogonal wave component and adifferent phase shift value upon traversal of wave energy in the otherorthogonal wave component; a circular polarizer for inverting theorientation of the electric field vectors positioned between thewave-guide termination and phase shifting means; and said incidentlinearly polarized received energy and said launched phase shiftedenergy being oriented in orthogonal planes to one another.
 9. Thecombination according to claim 8 wherein said phase shifting meansinclude semiconductor diode elements.
 10. The combination according toclaim 8 wherein said phase shifting means include digital latchingferromagnetic elements having binary remanent magnetization states. 11.A dual polarization microwave energy phase shifter comprising: squarewaveguide means for supporting and propagating electromagnetic waveenergy having electric field vectors oriented in a predeterminedpolarization plane and having orthogonal wave components; a plurality oforthogonally disposed semiconductor diode phase shiFting means disposedalong the longitudinal axis of said waveguide means for introducingapproximately one-half of a predetermined value of phase shift in oneorthogonal component of wave transmission traversing in one directionand the remaining one-half of the predetermined value of phase shiftupon incidence of the orthogonal component traversing in the reversedirection; conductive shorting means disposed at an end of saidwaveguide for reversing the direction of travel of substantially allenergy incident thereon; and a circular polarizer disposed between theshorting means and diode phase shifting means whereby one orthogonalcomponent emerges from said polarizer having a phase delay of 180*relative to the other component traversals in a forward and reversedirection.
 12. A dual polarization microwave energy phase shiftercomprising: a single port waveguide means for receiving and launchingcircularly polarized electromagnetic wave energy; solid-state phaseshifting means sandwiched between circular wave polarization means forconverting said circularly polarized waves to linearly polarized wavesdisposed within said waveguide; said conductive reflective terminationmeans enclosing the opposing end of said waveguide; said phase shiftingmeans introducing a predetermined value of phase shift in only onelinearly oriented wave component and substantially no electrical phaseshift in an orthogonally oriented wave component; and said received andlaunched wave energy having planes of polarization oriented orthogonalto one another.